If there's one thing Lucifer Morningstar hates, it's people pretending to be him.
He's already crossed paths with The Sinnerman, a cunning rival who adopted the devil's original shtick of offering favours to desperate people, but things are stepping up to the next level in Lucifer season 5.
Showrunners Joe Henderson and Ildy Modrovich are introducing Lucifer's twin brother, the archangel Michael, who can cause havoc for Mr Morningstar unlike anybody else.
Following his brother's exile back to hell, Michael descends from the heavens and steps into Lucifer's life, becoming acquainted with his beloved LAPD partner Chloe Decker.
Needless to say, Lucifer will be mighty cross when he finds out - and #Lucifans will be just as angry to see someone get in the way of Deckerstar's budding romance.
Although, perhaps there's a good reason behind Michael's devious actions, given that Henderson recently described Michael as "the hero of his story".
Read on for everything you need to know about Lucifer's brother: Michael.
Who is Michael in Lucifer season 5?
It's getting difficult to keep track of Lucifer's many siblings, given that we've already met Amenadiel, Uriel, Azrael and Remiel, but here comes yet another.
When Lucifer was forced to leave Earth at the end of season four, twin brother Michael spotted an opportunity to cause some trouble for his rival.
He comes down from heaven to claim Lucifer's life in Los Angeles for himself, becoming acquainted with LAPD regulars Chloe Decker, Ella Lopez and Dan Espinoza.
Of course, he's set himself a tough challenge. Lucifer has demonstrated many times in the past that he has a unique way of charming humans and a hatred for any who dare impersonate him.
Can Michael possibly hope to fool even those closest to him? One major clue that he isn't quite who he seems is that Michael's "gift from God" relates to people's fears, rather than their desires.
While season five, part one paints Michael in a rather antagonistic light, there is reason to believe we could sympathise with him more when part two arrives.
Speaking to Entertainment Weekly, showrunner Joe Henderson said: "The one thing I’ll say is that it was very important to us to make sure Michael was the hero of his story.
"That’s one of the things you don’t see a ton of in the first half, but it is something we will dig into later and understand his perspective and that is an element of it."
Is Michael from the Lucifer comic books?
Yes! Netflix's Lucifer series doesn't follow the events of the comic books particularly closely, but the writers have been known to pluck notable characters and adapt them in a way that fits their needs.
Michael debuted in the DC Comics universe back in 1990's The Books of Magic #1, created by writer Neil Gaiman and artist John Bolton.
He has always had a rivalry with Lucifer, dating back to his initial rebellion against God in heaven, where Michael led holy warriors against his brother and played a part in his defeat.
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